The widespread harvesting of lumber has increased the need for improved re-forestation practices. Of primary importance is planting the logged areas with new trees. It is common for re-forestation planting to be accomplished by manual labor, but such an approach is costly because of the difficulty of the work and the large amounts of area which must be covered. There have been numerous attempts to design a suitable tree seedling planter which is effective and efficient. To date all mechanized tree seedling planters have suffered from one or more limitation which deterred the acceptance of these implements by the lumber industry.
One problem which has been of particular difficulty is the need to place the seedlings at a specific depth in the soil. Seedlings placed too deep can become overlaid with soil or debris and not survive. If seedlings are not placed deep enough then root tissues can be left exposed and rendered ineffective at collecting moisture from the surrounding soil. This leads to drying of the seedlings and often to death. The problem of consistent seedling planting depth is made more difficult when planting in rough terrain. Relative movement between the tractor and seedling planter often lift or depress specific parts of the seedling planter thus changing the depth at which the seedlings are planted. This is particularly a problem when the planter is pitched with respect to the tractor about a transverse horizontal axis. Because of these difficulties the placement of seedlings by prior mechanized seedling planters has not been consistent, and a long felt need for better seedling depth consistency has plagued the lumber industry.
Another problem associated with seedling planting is inconsistency or inadequacy of packing the seedling into place. Seedlings have a better survival rate when the soil immediately about the root tissues is packed. This packing stabilizes the position of the seedling and improves the water uptake during the initial critical days after planting. The same problems of relative motion between the seedling planter and tractor also cause substantial variations in the degree to which soil is packed about the seedlings. Improved packing of soil about seedlings has also long been a desired goal in mechanized seedling planters.
Some prior art seedling planters utilized a set of one or more packing wheels which ran continuously behind the planting portion of the implement. Such an approach can form continuous depressions which initiate formation of gullies and increase erosion. The continuously contacting type of packing wheels also suffer significant wear and tear due to the constant working of ground which is often rocky and rough.
Some prior art seedling planters have also used coulters or other ground cutting disks to form a seedling furrow which sometimes ran continuously over the ground. The seedlings were intermittently placed along the furrow and packing accomplished after seedling placement. Such an approach to seedling planting requires that substantial amounts of soil be worked in order to place seedlings. However, the seedlings only require disruption of a relatively small amount of soil immediately about the seedling. The continuous furrow approach also wastes substantial amounts of energy and increases wear and tear on both the seedling planter and the pulling tractor.
Many prior art seedling planters were also manually operated with respect to many of the operating steps. The operator typically inserted the seedling into some type of planter element and then manually operated levers or other equipment to cause the machinery to proceed with the installation of the seedling into the ground. Accordingly, there is a need for an improved seedling planter which operates on a more automated basis with a minimum of required operation by a person.
In light of these and other considerations there remains a great need for a more efficient and effective automatic mechanized seedling planter. The current invention provides a novel seedling planter which is an improvement in the art of seedling planters.